Connector for timbers or the like



March 19; 1946. M. MILLER 2,396,717.

CONNECTOR FOR TIMBERS OR THE LIKE" 0 Filed Aug. 17, 1943 1 3. I 2mm Millar INVENTOR.

ATTORNEYS.

Patented Mar. 19, 1946 UNITED STATES PAT E OF F ILC eonsaeroeroierm Bsrts oitmatinee CIaims.

Thisinvention' relates to" a means for connectin'gj elements of. wood or wood; and metal struc tures; and has. for an object the provision of, means whereby the insufficiencies of ordinary bolting as a means of joining timbers and/or timbersand'metal' elements; are overcome.

Heret'oforedowelsor keys'have been used to: transmit shearing forces developed on the'con tacting, faces of connected'members; These have been'preformed" discs or rings which-have been embedded p'artiallyin' the face of each of two ad'- joining' timbers, and a clamping bolt has been extended through the centers" of these keys ordowels and" entirely through the. connected tim bers or" the like for the purpose of keeping the timbers from spreading because of the tendencyof the connectors to tilt or overturn when-subjectedi to the. forces' exerted" through the timbers'.

Connectors 'ofthe types described have certain disadvantages which the presentinvention is designed'to overcome. Forexample; the solid disk type of connector uses considerable weight of metal which. under" present. conditions, should. be avoided. The ring type of connector uses less metal but does-.notproperly. resist overturning because its edgesinaturally, cut or press into'the wood as the ringfconnectorbegins to overturn or tilt under application of the load." In'thisconnec' tion attention is directed to pages "Zj 8;"9111 12413 of a publication of the U. S. Department 'of Commeme 1 entitled Modern Connectors for "Timber Construction, 1933"; A": ring connector cannot" possibly come into'direct' contactwith the clamp ingbolt' forsupport thereby'overturning, and both the disc and ring types have disadvantages arising from the fact that the'meta'l connector must f t th -groove-"or;sinkage provided therefor with on-l-yverysma-ll clearancetolerance? Con sequently the -locations of the numerous grooves" 40" The need 55 shapes. of cbn'nectorswhioh might-be more vantageous for structural reasons.

The resent" nterlude has.- r 'r' its object the} provision of a means and also a method whereby the disadvantages heretofore pointed out are overcome. andit'. becomes possible quickly. without the'us ofskilld mechanics; to provide strong. connectors betweenltinibe rs or timbers and? metal elemen'ts whereby the parts canbe held' properly assembled following. any. desired relative angulariadjustment} the assembly being; maintained without danger of shearing, spreading or other undesirable developments which h'eretoforeh'ave been encountered.

With the foregoing and other objects in view which will'appear as the description proceeds, the inventionresides in certain features of construction and'icombinations'o'f parts'and in certain stepsof the method hereinafter more fully; described {and pointed out in the claims, it being understood that various changes may be made within the scope of the invention without departing'1froin' th'e'clairnsappended hereto.

the drawing; the preferred forfri' of the invention has been shown.

In said drawing; p H V b g I Figure. l'is an elevation of ilappingTend portions of some timbers-"provided 'with' my. improved-conhector. v

Figure '2 is'as'ction on line 2'2,'Figuretl.' Figure 3"is a sectiononline 3 3 FigureZI- Figure 4 is a section on line 4-4, FigurZI A's'h'a's'already been" p'ointedbut, the connector constitutin .th e various" typesof timbers" as well as wood' and metal 'mernberssuch as employed in building con- I struotioris an'd'other structures; Aigreatgvarijety of applications might be" illustrated and described but it.has been deemed desirable to SH vvin'the l'm ew th m! F dim l an as disclosed in' Figures 1" to 4 inclusive, three timhers-can be held"proprlylassembledby the means therein disclosed? In this term 3 of thefinvention which can. be. a.-roof truss or other structure wherein "one or. more timbers transmit thrust to other timbers,I there is shown an intermediate timber. I opposedqra e f which are engaged by sidetimbers! 2 and 3;

to receive. a clamping; bolt as hereinafter ex: plainedl Arecess or sinkage 5 is formed in each is invention is useful in joininga i' fe nde j th'rou'gliiall' .ofi'the timbers and is proportioned side of timber I and these are produced preferably by the use of a bit so that a circular recess is formed which is concentric with bore 4. Each recess or sinkage preferably is flared outwardly to a slight extent, the inclined walls being indicated at 6, and a desired number of flow holes I serve to connect the recesses 5. After the recesses or sinkages have been formed, each of them may be provided with a straight wall by removing portions of the timber with a chisel or the like to produce angles or corner portions as shown at 8. The resultant straight wall is indicated'at 9 and these walls 9 of the two recesses or sinkages are located directly opposite to each other.

The timbers 2 and 3 are substantial duplicates and each is formed in one face with a recess or sinkage l0 formed about the bore 4 and preferably, though not necessarily, shaped like the sinkages 5. These recesses or sinkages l0 however are arranged with their straight walls 0pposite to the walls 9. In other words the walls ll of recesses I0 and walls 9 of recesses 5 are located where they will receive the thrust'resulting from pressures transmitted through the beams in different directions respectively, as shown, for example, by the arrows in Figure 2. One or more tell-tale openings 13 and 14 are drilled into one timber 2, so as to open into its sinkage l0.

After the timbers or beams have been fabricated as described they are ready for assembly. Thetimber l is positioned between the timbers 2 and 3 so that the recesses 5 open into the recesses ID. A bolt I2 is then inserted into the bore 4 and the timbers are brought to a predeterminedangle relative to each other and the bolt is tightened. This bolt can be tubular for the greater portion of its length and'has an inlet [5 at one end while an outlet I6 is provided in the bolt at a point between the timbers l and 3, opening into space H].

The nextstep in the formation of the connector requires the introduction of a plastic material I'I into the bolt and from this it flows into and fills the spaces between the timbers provided by the recesses or sinkages 5 and [0. The material will move through the flowholes 1 until all of nectors of plastic will always fit perfectly and can be made to actually bond with the timbers at the contact surfaces. This can be effected, for example, by forming grooves IS in any desired 'shapes in selected surfaces and into which the plastic will flow. Any slight misalinement of the spaces in the timbers which is inevitable when time-wasting, exacting care in fabrication is not indulged in, will have no effect on the strength of the connection. Misalinement resulting from lumber shrinkage or swelling in the time interval between cutting and assembly will likewise cause no difiiculty whatsoever in the assembly of the various members or the strength of the connections. Deleterious indeterminate stresses in the immediate zone of the connection, heretofore caused bydriving into place ill-fitting metal connectors, are positively eliminated by this invention.

In'this structure the clamping bolt serves to restrain the connector from overturning because of its clamping action on all of the members. The connector is also restrained from overturning because it embeds a portion of the bolt and grips it.

Suitably devised reinforcing means can be provided in the connectors by embedding metal in the plastic as will be obvious. For the purpose of restraining the connectors against overturning they can be anchored to one or more of the connected members. For example screws 4| can be driven into the members at points where they will project into the key holding space. Thenswhen the plastic is forced into and fills the space it will become anchored by the screw or screws embedded therein, as will be apparent by referring to Figure 2.

Obviously should it be desired to so assemble the parts as to permit dismantling, it would 40 merely be necessary to jacket the bolts and line the spaces are filledand by observing the telltale holes l3 and M it can be determined when the filling operation has been completed. A weighted plunger can be mounted therein for free movement. This plunger 18 can serve as a signal device to indicate when the filling operation is complete and it can even be used for control ling the flow of plastic in any manner that might be obvious.

The plastic used as a filler can be of any suitable strong, hard drying material. Among other plastics used a strong cement of proper strength has been used successfully in a stiff state, this Portland cement having mixed with it suitable ingredients to insure strength and hardness when under stress.

After the plastic has hardened the assembly is complete and it will be, found that the connector thus formed will be free from all of the disadvantages heretofore present where other forms of connectors are used.

All faces of the recesses or sinkages can be inclined,as shown, or they can be otherwise shaped to give the most'advantageous connection for a particular purpose. The shape of the key or connector formed by the plastic is only limited by the tools and facilities for readily *cutting into the members to be connected; 'I 'he keys or conthe recesses with sheet material to prevent the plastic from adhering to the bolts and members. This is an obvious expedient.

By providing recesses which are not round but;

instead, have substantially straight thrust receiving walls, there is no danger of the timbers 'being split by the key or connector when subjected to excessive pressures. Thus one of the main'objections to the use. of circular dowels or connectors is eliminated. While the present improvements have been useful in the construction of parts of buildings, such as roof framing, etc'., they also can be employed in the construction of bridges and wherever skeleton framing is essential, or the, joining of several timbers to make a desired compound shape.

What is claimed is: l. The method of connecting structural elements which includes the steps of prefabricating one of the elements to provide recesses in opposed faces thereof communicating through a connect-.

' ing opening and to provide a telltale opening in a second element, drawing together said elements to substantially sealthe recesses toforma cavity opening through the tell-tale opening and asecond cavity opening'solely through said'conn'ectinto the other cavity to flu thesame and finally to overflow into thetelltale opening to indicate that the cavities are filled, said'secondcavity being closed against the outflow of plastic except through the connecting opening.

2. The method of connecting structural elements which includes the steps of prefabricating one of the elements to provide recesses in opposed faces thereof communicating through a connecting openirg, and to provide a telltale opening extending through one of the elements, drawing together said elements by means of a bolt having a recess extending into one end thereof and closed at its other end, thereby to form one cavity opening through the tell-tale opening and a second cavity having an outlet solely at the connecting opening said bolt being extended through the cavities and opening into said second cavity at a point remote from the telltale opening, and thereafter forcing a plastic material, capable of hardening, into one end of the recessed bolt for extrusion into said second cavity to first fill said cavity and then cause the plastic to overflow from said cavity through the connecting opening into the other cavity to fill the same and finally to overflow into the telltale opening to indicate that the cavities are filled, and that a series of spaced connectors have been formed by the plastic, each extending into two elements.

3. The method of connecting structural timbers which includes the steps of prefabricating one of the timbers to provide recesses in opposed faces thereof communicating through a connecting opening and prefabricating other timbers to provide recesses in one face of each of them and to form a telltale opening communicating with one of said recesses positioning the timbers with the recesses in communication to provide cavities at opposite sides of one of the timbers, drawing all of the timbers together to substantially seal the cavities, and finally forcing a plastic, capable of hardening, into one of the cavities at a point remote from the telltale opening to first fill said cavity and then cause the plastic to overflowfrom said recess through the connecting opening into the other cavity to fill the same and finally to overflow into the telltale opening to indicate that all of the cavities have been filled to provide connectors each extending into two timbers.

4. The method of connecting structural timbers which includes the steps of prefabricating 'one of the timbers to provide recesses in opposed faces thereof communicating through a connecting opening and prefabricating other timbers to provide recesses in one face of each of them and to form a telltale opening communicating with one of said recesses, positioning the timbers with the recesses in communication to provide cavities at opposite sides of one of the timbers, drawing the timbers together by means of a bolt having a recess extending into one end and positioned to open into one of the cavities at a point remote from the telltale opening, the other end of the bolt being closed, and finally forcing a plastic, capable of hardening, into the recessed end of the bolt for extrusion therefrom into one of the cavities at a point remote from the telltale opening to first fill said cavity and then cause the plastic to overflow from said cavity through the connecting opening into the other cavity to fill the same and finally to overflow into the telltale opening to indicate that the cavities are filled to form connectors each of which is extended into two timbers.

5. The method of connecting structural timbers which includes the steps of prefabricating one of the timbers to provide recesses in opposed faces thereof communicating through a connecting opening and prefabricating other timbers to provide recesses in one face of each of them and. to form a telltale opening communicating with one of said recesses, positioning an anchoring element'in one of the recesses, positioning'the timbers with the recesses in communication to provide cavities at opposite sides of one of the timbers, drawing all of the timbers together to substantially seal the cavities, and finally forcing a plastic, capable of hardening, into one of the cavities at a point remote from the telltale opening to first fill said cavity and then cause the plastic to overflow from said recess through the connecting opening into the other cavity to fill the same and finally to overfiow into the telltale opening to indicate that all of the cavities have been filled, said plastic constituting means for enveloping the anchoring element.

MAX MILLER. 

